间充质干细胞外泌体中的METTL16通过IGF2BP2依赖的GPX1 m6A修饰，促进急性髓系白血病中恶性进展及M2型巨噬细胞极化

Abstract

GPX1 was identified as a key hub gene in AML and closely linked to monocyte-macrophage differentiation. • GPX1 silencing suppressed AML malignancy, induced oxidative stress, and enhanced cytarabine sensitivity. • METTL16 mediated GPX1 m6A modification, which was recognized by IGF2BP2 to stabilize GPX1 mRNA. • METTL16 was highly enriched in exosomes derived from AML patient serum and AML mesenchymal stem cells. • METTL16-deficient exosomes reversed pro-tumoral effects and inhibited M2 polarization by downregulating GPX1. Background Acute myeloid leukemia (AML) progression relies on complex crosstalk with the bone marrow microenvironment, particularly M2 macrophage polarization. Exosomes mediate intercellular communication, while N6-methyladenosine (m6A) modifications drive tumor malignancy. However, the role of exosomal m6A regulators in coordinating AML progression and macrophage polarization remains unclear. Methods Integrated bioinformatics combining transcriptomics, weighted gene co-expression network analysis (WGCNA), and single-cell RNA sequencing identified key genes in AML. mRNA and protein expression levels were detected by quantitative real-time polymerase chain reaction and Western blotting assays. In vitro assays evaluated AML cell proliferation, apoptosis, oxidative stress, and drug sensitivity. Macrophage polarization was assessed using Transwell co-culture systems. Exosome isolation, m6A RNA immunoprecipitation, RNA immunoprecipitation, and dual-luciferase reporter assays elucidated the underlying molecular mechanism. A xenograft mouse model assay was performed to analyze the effects of methyltransferase-like 16 (METTL16)-deficient exosomes and glutathione peroxidase 1 (GPX1) overexpression on tumor formation. Results GPX1 was identified as a hub gene in AML. Its expression was significantly upregulated in AML and closely linked to monocyte-macrophage differentiation. Functionally, GPX1 silencing suppressed AML cell malignancy, induced oxidative stre